Batteries, as a source of electric energy, can be mounted on a variety of devices to provide stable voltage and stable current for the devices, and achieve stable power supply for a longer time. With the development of science and technology, the structure of a battery becomes simpler and simpler, allowing for more ease for carrying and simpler and more convenient charging and discharging operations. A lithium-ion battery is a secondary battery (a battery that can be recharged multiple times). It mainly relies on the movement of lithium ions between positive electrodes and negative electrodes to operate. The lithium-ion battery is a representative of the modern high-performance batteries.
The battery life of a lithium-ion battery can be seriously affected when it is used in low-temperature environments. At present, it is not feasible to charge the lithium-ion battery at an ambient temperature below 0 degree, and it is not feasible to carry out fast-charging at an ambient temperature between 0 degree and 10 degrees. Otherwise, lithium precipitation can occur, causing the battery to fail and even accidents. During battery discharging, it is not feasible to discharge and use the lithium-ion battery at an ambient temperature below −20 degrees, and high current discharge between −20 degrees and 0 degree is not recommended. Otherwise, performance of the battery attenuates severely.
At present, there are no preheating or charging-heating-insulation devices for lithium-ion batteries. The existing preheating protection for lithium batteries is achieved generally by wrapping a heat source made up of heating resistors on the surface of a lithium battery, which forms a lithium battery that can be preheated. Not only does this type of lithium-ion batteries have a higher cost, but the temperature of the heat source covering the surface of the battery also cannot be well controlled, which can also damage the battery and affect its battery life.